You eat healthy that day and may be exercise a little. - exercise may be in terms of taking the stairs instead of the elevator or you go to the gym during lunch. You finish up the 3-meetings-in-a-row run before you know it. Towards the end of the working hours, if you feel like you've completed 80% of your to-dos and you have no emergencies to handle you should feel lucky.
And if you are so priviledged like me, you may get the chance to play with your mates and laugh a little at the end of the day. When you joke around with your boss and collegues and don't feel stuck in your cubicle. You should take a longer pause and think: it was a better day!
So, appreciate it!